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Stabilizing Spiral and Spatiotemporal Chaos in External Centric Field

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Communications in Theoretical Physics 2006年第6期45卷 1035-1041页

作者： ma Jun wang chun-Ni PU Zhong-Sheng LI Yan-Long School of Science Lanzhou University of Technology Lanzhou 730050 China

In this paper, a scheme of spatial perturbation is introduced into a class of excitable media, which are described by two-dimensional partial-differential equation models. Inertial acentric force （or centrlpetal force）, which is generated by circumgyrating the whole system vs. a right axis, is used to disturb the system. The whole system becomes homogeneous as soon as the spatial perturbation is imposed on even when the noise is in consideration. The principle of this scheme is confirmed based on the theory of hopf bifurcation and numerical simulation.

关键词： pattern spiral spatiotemporal chaos inertial acentric force

The Symmetry Energy from the Neutron-Rich Nucleus Produced in the Intermediate-Energy 40,48Ca and 58,64Ni Projectile Fragmentation

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Chinese Physics Letters 2012年第6期29卷 90-93页

作者： ma chun-wang PU Jie wang Shan-Shan WEI Hui-Ling Department of Physics Henan Normal UniversityXinxiang 453007

In the framework of a modified Fisher model,using the isobaric yield ratio method,we investigate the fragments produced in the 140 A Me V 40,48Ca+9Be and 58,64Ni+9Be projectile fragmentation *** different approximation methods,asym/T (the ratio of symmetry-energy coefficient to temperature) of symmetric and neutron-rich fragments are *** is found that asym/T of fragments depend on the reference nucleus and the neutron excess of *** asym/T of the isobar decreases when the neutron-excess of the isobar increases,while for a fragment with the same neutron-excess,asym/T increases as the mass of the fragment increases but saturate when the mass of the fragment becomes larger.

关键词： excess symmetry fragmentation

Synthesis and characterization of poly[(4-vinylphenyl)dimethyl-silane]-b-polybutadiene-b-poly[(4-vinylphenyl)dimethylsilane](PVPDMS-b-PBd-b-PVPDMS)

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Chinese Chemical Letters 2011年第11期22卷 1371-1374页

作者： Hong Wei ma Bai wang chun Qing Zhang Yang Li Yan Ming Hu Yu Rong wang Liaoning Key Laboratory of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian Liaoning 116024 China

The novel functionalized triblock copolymers,poly[（4-vinylphenyl）dimethylsilane]-b-polybutadiene-b-poly[（4-vinylphenyl）-dimethylsilane] （PVPDMS-b-PBd-b-PVPDMS）,were synthesized by anionic polymerization method using high vacuum technique. The hydrocarbon-soluble dilithium initiator synthesized from l,3-di[l-（methylphenyl）ethenyl]benzene（MPEB） was used to synthesize polybutadiene（PBd） precursors and the triblock copolymers in the presence of *** precursors and copolymers were characterized by size exclusion chromatography（SEC）,~1HNMR and DSC techniques.

关键词： Anionic polymerization Functionalized triblock copolymers High vacuum technique

An efficient synthesis of 1,5-benzodiazepine derivatives catalyzed by boric acid

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Chinese Chemical Letters 2009年第8期20卷 905-908页

作者： Xin Zhou Mei Yue Zhang Shu Tao Gao Jing Jun ma chun wang Chao Liu Hebei Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benign and high yielding. ？2009 chun wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 1,5-Benzodiazepincs o-Phenylenediamines Boric acid Synthesis

Surface and Volume Symmetry Energy Coefficients of a Neutron-Rich Nucleus

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Chinese Physics Letters 2012年第9期29卷 32-35页

作者： ma chun-wang YANG Ju-Bao YU Mian PU Jie wang Shan-Shan WEI Hui-Ling Department of Physics Henan Normal UniversityXinxiang 453007 Department of Life Sciences and Technology Xinxiang Medical UniversityXinxiang 453003 Department of Nuclear Physics Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800

Using an isobaric method,the symmetry-energy coefficient(asym)of a neutron-rich nucleus is obtained from experimental binding *** shell effects are shown in a^(*)_(sym)/A≡4asym/A of nuclei.A(sub)magic neutron magic number N=40 is suggested in a very neutron-rich nucleus,and a^(*)_(sym)/A of a nucleus is found to decrease when its mass *** a^(*)_(sym)/A of a very neutron-rich nucleus with large mass *** volume-symmetry coefficients(b_(v))and surface-symmetry coefficients(b_(s))of a neutron-rich nucleus are extracted from a sym*/A by a correlation a^(*)_(sym)/A=bv/A-b s/A^(4/3).It is found that bv and bs decrease when the nucleus becomes more neutron-rich,and tend to saturate in the very neutron-rich nucleus.A linear correlation between b v and bs is obtained in nuclei with different neutron-excess I,and bv of I>7 nuclei is found to coincide with the results of infinite nuclear matter a sym=32±4 MeV,and bs/bv of the nucleus is found to coincide with the results of the finite-range liquid-drop model results.

关键词： symmetry infinite coincide

Effect of increased hepatic platelet activating factor and its receptor portal hypertension in CCl_4-induced liver cirrhosis

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World Journal of Gastroenterology 2006年第5期12卷 709-715页

作者： Yong-Ping Yang Xue-Mei ma chun-Ping wang Jun Han Yin-Ying Lu Yi Xiang Shu-Hui Su Yong-Yi Feng Department of Gastroenterology 302 Hospital ofPLA Beijing 100039 China

AIM： To evaluate the changes in hepatic platelet activating factor （PAF） and its receptors and their effect on portal pressure of cirrhotic rats induced by CCh. METHODS： A model of liver cirrhosis was replicated in rats by intra-peritoneal injection of CCh for 8 wk. We determined the effect of hepatic PAF and its receptor level on portal and arterial pressure by EIA, saturation binding and RT-PCR technique. RESULTS： Compared to control rats, cirrhotic rats had higher hepatic PAF levels and output as well as higher plasma PAF levels （P〈0.01, P〈0.01, P〈0.05, respectively）. Both hepatic PAF receptor mRNA levels and PAF binding were nearly 3-fold greater in cirrhotic rats （P〈0.01）. Portal injection of PAF （1 g/kg WT） increased the portal pressure by 22% and 33% in control and cirrhotic rats, respectively. In contrast, the arterial pressure was decreased in the both groups （54% in control rats and 42% in cirrhotic rats）. Injection of the PAF antagonist BN52021 （5 mg/kg WT） decreased the portal pressure by 16% in cirrhotic rats but had no effect in the control rats. CONCLUSION： The upregulation of the PAF system contributes to hepatic hemodynamic and metabolic abnormalities in drrhosis, and the increased release of PAF into the circulation has impacts on the systemic hemodynamics.

关键词： Platelet activating factor PAF receptors Endothelin Portal hypertension Cirrhosis

Optimum design of a polymer electro-optic microring resonator switch

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Optoelectronics Letters 2007年第6期3卷 423-427页

作者： YAN Xin ma chun-sheng wang Xian-yin Zhang Da-ming Liu Shi-yong State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin UniversityChangchun 130012 China

Novel transfer functions are presented for a polymer electro-optic mieroring resonator switches. The resonating process ot the light in the microring is simulated using the formulas. Then the optimization of the structural parameters is performed, and the characteristics are analyzed, such as the resonance time, output spectrum, operation voltage, insertion loss and crosstalk were analyzed. The simulation results show that the designed device exhibits favorable switching functions.

关键词：集成光学器件聚合物电子光学共振器

Isolation and Complete Nucleotide Sequence of the Measles Virus IMB-1 Strain in China

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Virologica Sinica 2010年第6期25卷 381-389页

作者： Shao-hui ma Li-chun wang Jian-sheng LIU Hai-jing SHI Long-ding LIU Qi-han LI Institute of Medical Biology Chinese Academy of Medical Sciences and Peking Union Medical College Kunming 650118 China

The complete nucleotide sequence of the measles virus strain IMB-1,which was isolated in China,was *** in other measles viruses,its genome is 15,894 nucleotides in length and encodes six *** full-length nucleotide sequence of the IMB-1 isolate differed from vaccine strains (including wild-type Edmonston strain) by 4%-5% at the nucleotide sequence *** isolate has amino acid variations over the full genome,including in the hemagglutinin and fusion *** report is the first to describe the full-length genome of a genotype H1 strain and provide an overview of the diversity of genetic characteristics of a circulating measles virus.

关键词： Complete nucleotide sequence Genotype H1 Measles virus (MV)

一种低损耗的对称双楔形太赫兹混合表面等离子体波导

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物理学报 2020年第7期69卷 74-82页

作者：王芳张龙马涛王旭刘玉芳马春旺河南师范大学电子与电气工程学院新乡453007 河南省光电传感集成应用重点实验室新乡453007 河南师范大学物理学院新乡453007

本文研究了一种适用于太赫兹频段的对称双楔形混合等离子体波导.采用有限元法对其混合模式特征进行数值模拟,阐述了波导的传播长度、归一化有效模场面积和品质因子等特性随波导几何参数的变化规律.结果表明,对称双楔形混合等离子体波导... 详细信息

本文研究了一种适用于太赫兹频段的对称双楔形混合等离子体波导.采用有限元法对其混合模式特征进行数值模拟,阐述了波导的传播长度、归一化有效模场面积和品质因子等特性随波导几何参数的变化规律.结果表明,对称双楔形混合等离子体波导在太赫兹频段可获得良好的模场约束能力和低损耗特性,在有效模场面积达到λ2/10280时,传播长度达到51 × 103 μm.波导参数最优时的平行对称楔形波导在忽略波导间串扰时,波导间距小于16 μm时的耦合长度约为8958 μm.通过对比发现,相比于先前的对称微楔形波导结构和对称蝴蝶结波导结构,对称双楔形混合等离子体波导在传输特性和耦合特性方面都具有更大的优势,将在光学力捕获、生物分子传输以及高密度集成电路设计等方面具有潜在的应用前景.

关键词：混合等离子波导表面等离子体传输特性耦合特性